If you are affected (i.e. you see Alfred's CPU usage spike to 100%), Activity Monitor will show two Python processes like this (choose View > All Processes, Hierarchically), with the bottom one at ~99% CPU (this screenshot is actually of a non-misbehaving workflow):

Download and run this workflow, which will update any old versions of Alfred-Workflow in your installed workflows.

That should get your workflows working again until the workflow developers can push official fixes.

Edited April 8, 2017 by deanisheReplace IPB with an image service that works